“We do know the tornado that touched down in Coon Rapids and Blaine was weaker. It was classified as an EF1 and the Hugo tornado was classified as a EF3. The same updraft was passing over these areas; it just produced different touchdowns.”

What was the difference between the two?

“The tornado that touched down in Hugo — the more intense one — was wider. It was an eighth-of-a-mile wide, which is twice as long as the one that touched down in Coon Rapids, which was 100 yards wide. Usually, what we see is the wider the tornado, the stronger it is.”

What was unique about Sunday’s tornadoes?

“What is troubling about Sunday is that it was really our first severe weather of the season, and it already started with a major tornado in the confines of the metro.”

How can a tornado hit one house and leave others unscathed?

“That’s just the path the tornado takes. It’s as simple as the houses in one area got hit, and those you still see standing were missed by the tornado itself. It’s a very tight area of strong winds that are rotating. Outside of that wind, it can be relatively calm.”

Did the path surprise you?

“Not really. This storm followed a pretty straight path. It didn’t meander. It was a little bit northwest to southeast, but it was a straight path.”

Sunday was not only one of the first warm days of the season, it was humid. Did those two elements play a big part?

“Absolutely. It was the first day in the 80s and the first muggy day. It’s just as basic as that storms are made out of water, and you have to have a lot of water in the air. And the warmer the air, the more water it holds.”

What caused it to touch down?

“That’s a lot of what we simply don’t know about tornadoes. Why does it touch down in exactly the spot it does? We know the (conditions) necessary to bring the tornado to the ground were present through that whole area. That’s part of why the weather service goes out and does these surveys — to get extra information so we can learn more and then compare that with the radar images to see what was happening at that exact time.”

Are we in “Tornado Alley”?

“Absolutely. It includes much of the central U.S., and it goes as far as Minnesota from the Gulf of Mexico. It includes, obviously, all the Plains states and over to about Michigan, maybe at the eastern-most extent, Illinois, the Ohio River Valley and south of there.”

There have been a number of deadly tornadoes this year in the U.S. Why?

“One of the things that’s contributed to the particularly active severe weather season is the La Nina cycle that we’re in. And for a little brief background — it’s the opposite of El Nino. … Where El Nino is a warming of the water off the coast of Peru, La Nina is the opposite — it’s cooler-than-normal Pacific water. And that has been linked to a more active severe weather season than usual in the U.S. As far as Minnesota goes, it’s not as specific of a correlation because we’re on the northern end of Tornado Alley. But in a typical severe weather season, all that stuff marches north, so one could conclude we also would have a little bit more active season than normal.”

What are some of the most common myths about tornadoes?

“The big one is that tornadoes can’t hit downtown areas. And I always throw out examples to people — Salt Lake City had a tornado, Miami had a tornado, Atlanta just this winter had a tornado. It has nothing to do with a building — it might alter the shape of the tornado a little bit, but that’s all. What’s happening in these organized storms is happening thousands of feet up and totally irrelevant of what’s going on on the ground. Whether it reaches the ground has to do with the surface wind and not necessarily a building. A building can alter a surface wind a little bit in a very small area, but it doesn’t have enough of an effect to stop a tornado from developing.

“Another myth is … to open windows in the house so the air moves through. That just doesn’t happen. The pressure differences and the force are so strong, a window is essentially a little hole in your house. It makes no difference.”

Is it true that hail usually precedes a tornado?

“Hail is proportional to how strong the updrafts are in a thunderstorm. But a storm can produce hail without having rotating updraft, which could produce a tornado also. Whenever you have hail, it does show the storm is pretty intense. Because for ice to fall to the ground, you have to have strong air moving vertically upward. And that air has to be strong enough to keep the ice suspended in air so that water can freeze onto the ice, and it can grow bigger and bigger.”

As you comment, please be respectful of other commenters and other viewpoints. Our goal with article comments is to provide a space for civil, informative and constructive conversations. We reserve the right to remove any comment we deem to be defamatory, rude, insulting to others, hateful, off-topic or reckless to the community. See our full terms of use here.

More in News

Drivers along Ayd Mill Road in St. Paul call it one of the most pockmarked roadways in town. Winter melt, age, traffic intensity, deferred maintenance and questionable construction all have taken their toll. St. Paul city officials are continually grappling with the challenge of funding road repair for a growing residential and business population. Outsiders sometimes make unfair comparisons to...

St. Paul Saints general manager Derek Sharrer's stomach was doing backflips as he watched No. 16 seed Maryland-Baltimore County beat No. 1 overall seed Virginia. The team he’s in charge of was about to be out $10,000.

A marker on the Hillcrest Golf Course proclaims the Hillcrest Knoll to be Ramsey County's highest hilltop, though folks in Arden Hills and Shoreview might dispute it. Soon, the 1920s-era golf course may have another claim to fame -- housing, and lots of it. At Larpenteur Avenue and McKnight Road on the city's Greater East Side, Hillcrest represents 112 acres...

AUSTIN, Texas (AP) — The hunt for the serial bomber who has been leaving deadly explosives in packages on Austin doorsteps took a new, more sinister turn Monday when investigators said the fourth and latest blast was triggered along a street by a nearly invisible tripwire.